1. Field of the Invention
The invention relates to an apparatus, a method, and a program for storing and retrieving data showing a hierarchical structure such as product structure, organization structure, or the like. More particularly, the invention relates to an apparatus, a method, and a program in which when data that is used changes, stored data is consequently changed.
2. Description of the Related Arts
A method of handling a product structure which is changed has been disclosed as a change history management of production in JP-A-1999(Heisei 11)-66139 (Patent Document 1). In the invention, such a management is called an efficient date management.
A method of handling a product structure which is changed has been disclosed as a generation management and a version management in the Official Gazette of Japanese Patent No. 3547990 (Patent Document 2).
A method whereby in response to a change in production, data before the change and data of the changed portion after the change are managed and the data before the change and the data after the change are retrieved has been disclosed in the Official Gazette of Japanese Patent No. 3598026 (Patent Document 3). In the invention, such a management is called an efficient date management.
A general database management system has a function of recording a change history of data.